X-ray CT is the de facto standard for volumetric inspection. Parts, or any other object, person, or animal to be analyzed, are typically placed into a stationary cabinet where the part is rotated between an x-ray source and an x-ray detector. Parts may also be slowly marched through a rotating ring containing an x-ray source and x-ray detector.
Thousands of x-ray shots are taken of the part at unique angles of incidence. A volume image may be formed from these x-ray shots through a process called reconstruction. Conventional commercial reconstruction techniques use processes based on the Radon transform, which is why a large number of x-ray shots are required. The volume image may then be rendered, sliced, or dissected during analysis to measure features or diagnose failures in the part under inspection.
Conventional x-ray CT cannot be used for parts that do not fit within the cabinet or ring. Some x-ray systems exist that are advertised as “portable.” However, they are heavy, dedicated systems that require the part under inspection to be manipulated through a ring. While such systems may find some application, they are generally limited and impractical. For parts in the field, it may only be reasonable, or even possible, to capture a limited number of shots at unique angles of incidence compared to the thousands of shots required in a conventional CT scan, and it may be difficult or impossible to exploit rotational symmetry. Also, a large number of unique x-ray shots may not be possible. Accordingly, an improved x-ray process and system may be beneficial.